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Rev Author Line No. Line
2 - 1 
Q	= 0
2 
N	= 1
3 
D	= 2
4 
CC	= 3
5 
TMP	= 11
6 
 
7 
TEXT	save<>(SB), 1, $0
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	MOVW	R(Q), 0(FP)
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	MOVW	R(N), 4(FP)
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	MOVW	R(D), 8(FP)
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	MOVW	R(CC), 12(FP)
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	MOVW	R(TMP), R(Q)		/* numerator */
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	MOVW	20(FP), R(D)		/* denominator */
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	CMP	$0, R(D)
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	BNE	s1
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	MOVW	-1(R(D)), R(TMP)	/* divide by zero fault */
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s1:	RET
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TEXT	rest<>(SB), 1, $0
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	MOVW	0(FP), R(Q)
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	MOVW	4(FP), R(N)
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	MOVW	8(FP), R(D)
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	MOVW	12(FP), R(CC)
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/*
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 * return to caller
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 * of rest<>
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 */
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	MOVW	0(R13), R14
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	ADD	$20, R13
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	B	(R14)
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TEXT	div<>(SB), 1, $0
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	MOVW	$32, R(CC)
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/*
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 * skip zeros 8-at-a-time
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 */
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e1:
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	AND.S	$(0xff<<24),R(Q), R(N)
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	BNE	e2
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	SLL	$8, R(Q)
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	SUB.S	$8, R(CC)
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	BNE	e1
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	RET
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e2:
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	MOVW	$0, R(N)
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loop:
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/*
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 * shift R(N||Q) left one
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 */
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	SLL	$1, R(N)
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	CMP	$0, R(Q)
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	ORR.LT	$1, R(N)
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	SLL	$1, R(Q)
56 
 
57 
/*
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 * compare numerator to denominator
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 * if less, subtract and set quotent bit
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 */
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	CMP	R(D), R(N)
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	ORR.HS	$1, R(Q)
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	SUB.HS	R(D), R(N)
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	SUB.S	$1, R(CC)
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	BNE	loop
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	RET
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TEXT	_div(SB), 1, $16
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	BL	save<>(SB)
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	CMP	$0, R(Q)
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	BGE	d1
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	RSB	$0, R(Q), R(Q)
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	CMP	$0, R(D)
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	BGE	d2
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	RSB	$0, R(D), R(D)
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d0:
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	BL	div<>(SB)		/* none/both neg */
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	MOVW	R(Q), R(TMP)
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	B	out
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d1:
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	CMP	$0, R(D)
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	BGE	d0
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	RSB	$0, R(D), R(D)
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d2:
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	BL	div<>(SB)		/* one neg */
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	RSB	$0, R(Q), R(TMP)
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	B	out
88 
 
89 
TEXT	_mod(SB), 1, $16
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	BL	save<>(SB)
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	CMP	$0, R(D)
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	RSB.LT	$0, R(D), R(D)
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	CMP	$0, R(Q)
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	BGE	m1
95 
	RSB	$0, R(Q), R(Q)
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	BL	div<>(SB)		/* neg numerator */
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	RSB	$0, R(N), R(TMP)
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	B	out
99 
m1:
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	BL	div<>(SB)		/* pos numerator */
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	MOVW	R(N), R(TMP)
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	B	out
103 
 
104 
TEXT	_divu(SB), 1, $16
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	BL	save<>(SB)
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	BL	div<>(SB)
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	MOVW	R(Q), R(TMP)
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	B	out
109 
 
110 
TEXT	_modu(SB), 1, $16
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	BL	save<>(SB)
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	BL	div<>(SB)
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	MOVW	R(N), R(TMP)
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	B	out
115 
 
116 
out:
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	BL	rest<>(SB)
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	B	out